Rust By Example

To link a crate to this new library, the extern crate declaration must be
used. This will not only link the library, but also import all its items under
a module named the same as the library. The visibility rules that apply to
modules also apply to libraries.

# Where library.rlib is the path to the compiled library, assumed that it's
# in the same directory here:
$ rustc executable.rs --extern rary=library.rlib && ./executable
called rary's `public_function()`
called rary's `indirect_access()`, that
> called rary's `private_function()`